


Lamia Den

by DeckofDragons



Category: Undertale (Video Game)
Genre: Ecto-biology, Forced Arousal, Forced Pregnancy, Hemipenes, Kidnapping, Lamia Slim, Mpreg, Multiple Orgasms, Other, Oviposition, Rape, Size Kink, cum kink, neck biting, skelepreg, snake venom
Language: English
Status: Completed
Published: 2018-08-31
Updated: 2018-08-31
Packaged: 2019-07-04 22:23:38
Rating: Explicit
Warnings: Rape/Non-Con
Chapters: 1
Words: 5,030
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/15850608
Author URL: https://archiveofourown.org/users/DeckofDragons/pseuds/DeckofDragons
Summary: Stretch tries to scare off the lamia that's been following him around but ends up in its den instead.





	Lamia Den

**Author's Note:**

  * For [alicedragons](https://archiveofourown.org/users/alicedragons/gifts), [Sora_Tayuya](https://archiveofourown.org/users/Sora_Tayuya/gifts).



Stretch had nicknamed the lamia ‘Slim’ as a misnomer, it was far too large to ever be close to what could be considered slim. Its upper half was that of a skeleton monster, its lower half was a long burnt-orange snake. One of its sharp fangs were missing, with a small crack running up from where it had been. It bore other scars too; it had seen its share of battles and presumably won more often than not. Which made it even worse as far as Stretch was concerned.

Blueberry had suggested he name after he’d told him about it and how it followed him every time he had to walk through the woods – presumably its territory – for whatever reason even though he’d said in no uncertain terms that he didn’t like it – he didn’t like snakes in general, giant half snakes were even worse.

Moving away was unfortunately not an option, he didn’t have the money to afford a new place and he hadn’t been living here long. He could move back in with Blueberry but would rather not, they’d spent their whole _lives_ living in the same house, he needed some independence. He would’ve moved in with Fell but Fell had left to attend a faraway fancy cooking college and wouldn’t be back anytime soon. Meaning Stretch was forced to put up with the damn snake by himself, he wasn’t a child he could handle it. Next time he caught it following him he’d charge at it and hopefully scare it off and then he wouldn’t have to worry about it sneaking into his house and eating him while he slept anymore.

One evening after a car trip to the grocery store he went out of his way to take a while to bring everything inside from his car. As expected it wasn’t long before Slim appeared in the tree-line, watching him. He kept an eye on it as he finished putting the groceries in the house. It had never made any move to attack him but that might be because it was waiting for the prefect chance to strike. Its eyes certainly never seemed to leave him so that had to be it.

After the groceries had been put away Stretch went back outside. Slim was still there and still watching. It was now or never. He’d grabbed a broom from the kitchen, he didn’t want to hurt it so he wouldn’t use magic on it unless he had to, he just wanted to assert his dominance and scare it off. He could do it, ever since he’d moved in here he’d been killing all the spiders he’d found all by himself with the very broom he held in his hands now.

He crept closer, watching the lamia as intently as it watched him. It didn’t move, if it wasn’t for the bright magic making up its bone and white bones he probably wouldn’t have ever been able to spot it watching him.

Once he was an uncomfortably short distance away from it he raised the broom high above his head and charged, shouting his loudest ululating battle cry. It flinched and jerked backwards, encouraging him to keep shouting and running at it. It was working! It was afraid of him! It…

Stretch tripped. He landed hard, his battle cry cutting off with a grunt of pained surprise as he dropped his broom. Sharps waves of pain shot through his ankle. It wasn’t broken – or at least Stretch hadn’t heard or felt any bones breaking – but it was _badly_ sprained.

He groaned as pushed himself up with his hands. The lamia was _right_ in front of him now. It was _much_ bigger close up. How had it moved so fast and quietly?

Stretch scrambled to stand again but the horrible pain in his ankle killed that idea. “Stay back,” he said through gritted teeth. He could try to teleport away but his ankle hurt too much for him to focus on such complex magic, curse his low pain tolerance.

Slim slithered close and bent down to scoop him up into its arms. He squirmed but every little movement sent another stab of pain through his ankle, leaving him to hang limp as it held him to its chest bridle style. He was an idiot, he’d doomed himself. It was going to eat him now and that would be the end of it.

It hissed, its tongue flicking out to tickle Stretch’s face. He turned his face as far away from as he could which exposed his neck enough for it to bite him. He squeaked as its fangs sank in. It didn’t hurt but he could feel it release something into him, something warm and tingly. Venom! Oh gosh, he was going to die, and it was going to hurt and it was his own damn fault.

Slim flicked its tongue over his face again and pressed its forehead to his, nuzzling it. He flinched and trembled but it did nothing else. After straightening it started moving deeper into the woods, bringing him with it.

How fast would it take for its venom to kill him? It was spreading rapidly down his neck, nearing his soul. It wasn’t long before it hit. He didn’t die though, instead the tingling warmth started spreading faster. Soon his whole body pulsed with heat. It wouldn’t have been unpleasant in different circumstances and it soothed the pain in his ankle quite a bit. But magic was gathering in his pelvis; it was making him aroused. He’d heard of poisons and venoms that did that so he shouldn’t be too surprised but he’d _really_ rather not be aroused right now.

It grew stronger as Slim continued to carry him to wherever the fuck it was taking him. The magic in his pelvis took shape into a pussy. It took shape in his middle too, forming a womb attached his pussy. _Why_? Neither would go away no matter how hard he tried to dispel them and he was soon forced to give up and just hang limply in Slim’s arms, panting with arousal and fear. Hopefully his torment would be over soon.

Eventually they ended up in a cave. It might have taken five minutes to get there or five hours there was no way to tell for sure. The inside was cool – a relief on Stretch’s heated bones – but reeked of reptile, a musty unpleasant scent. This had to be the lamia’s den, meaning Stretch’s chance to escape was gone now.

Slim hissed as it carried Stretch to the back, around a bend. There was a large pile of blankets, arranged to resemble an oversized nest. Slim laid him gently in the middle.

If this was a nest did that mean it had babies? Were the babies going to eat him? Stretch snapped his head to the left and then right. Unless the babies were small enough to hide effectively between the layers of blankets and other soft things there weren’t any around. That didn’t mean he wasn’t about to get eaten though.

Slim grabbed his leg and pulled it up to examine his injured ankle. A long burnt-orange forked tongue flicked out of its mouth, brushing against Stretch’s bones and making him shudder.

The lamia removed his shoe, tossing it to the side to get an even better look, giving Stretch a better look too. It didn’t appear to be as bad as how it felt even with the numbing affect brought on by the arousing venom but it would still be a while before he could walk on it again, assuming he even survived the next few moments or hours.

Apparently deciding it didn’t care about his ankle much, Slim placed Stretch’s leg back down, moving it with unexpected care. Its tongue flicked out again as Stretch cowered, even if he could run freely it was between him and the exit, getting past it would be hard if not impossible.

He flinched as it bent over again, this time to remove his other shoe and then grab the hem of his shorts. It pulled them partially down before Stretch could push its hands away. Unfortunately it was enough to leave his pelvis bare, making him gasp as the air hit his aching magic.

He jerked away with a whimper but its grip on his pants meant he was helping it to remove them so he froze. “Stop,” he said though clenched teeth as if it could ever understand him.

It stared at his privates as if they were a fascinating treasure. Was it about to… _Surely_ not… right? They were _entirely_ different species; their parts probably weren’t compatible and Stretch would rather _die_ than morph his to be so.

After several awful seconds it shook its head and finished removing Stretch’s pants, ignoring his attempt to stop it with his hands but careful not to jostle his ankle much as it pulled them off. It then grabbed his wrist with one hand so it could pull him up and grab the back of his hoodie and tug it up.

It took longer for it to remove that but it did and Stretch only put a token effort to stop it. He didn’t mind being naked much, he was hot enough that it felt nice and the arousal coursing through him made him feel weak. The way it looked at him though after tossing his clothing to the side made him curl up into a ball with a whimper.

“Please don’t hurt me.” Maybe it could at least understand his tone of voice and might show mercy if he was pitiful enough. “I’m not…” He cut off, choking on his words.

Slim was naked too of course – lamias never wore clothing as far as he could tell – meaning the… magic bits that grew off its body were unmistakable. Dicks! _Two_ of them and they were erect; it _was_ about to rape him.

Stretch backpedaled away, almost not feeling the pain in his ankle. He pressed himself up against the wall and closed his legs tight. He shook his head and for good measure waved his hands in a negative gesture too; such were universal signals for ‘no’, right?

Whether they were or not Slim didn’t seem to care as he slithered closer, blocking Stretch’s route to the exit even more. It flicked its tongue out, making another soft hissing sound. Did the sounds it made _mean_ anything though? Like its own form of speech or was it a mindless animal _completely_ incapable of rational thought?

It loomed over Stretch and grabbed his wrist to pull him closer and then back towards the center of the nest. Curled up in a ball, he pulled away from it, straining his arm until it hurt. But it didn’t seem to care as once in the center of the nest once more it wrapped the snake part of its body loosely around him. It was long enough to fully encircle him without touching him.

Still holding him up by his wrist, Slim leaned over to nuzzled its face into Stretch’s neck, its tongue brushing against Stretch’s neck bone right where it had bit him. Shuddering, he let out a pathetic whimper. How close it was seemed to make the arousal coursing through his body worse, almost unbearable, certainly bad enough that he didn’t feel capable of fighting. Not that he would’ve gotten far if he had, even not drugged and uninjured it was still much bigger and stronger than him.

Straightening, Slim pulled him over so that he was leaning back against its tail, near where it beginning tapering off towards the end. It curled its body tighter in so that its cocks were pointed directly towards him, grabbed his legs to pulled them up at an uncomfortable angle and apart to put itself between them.

“Please j-just one,” Stretch panted out with a whimper as a tear ran down the side of his face. He couldn’t fight it off and the pounding arousal coursing through him wasn’t letting him try very hard but he _couldn’t_ take both of its cocks at once, he wasn’t meant for that kind of mating. “Not both _please_ , you’ll break me.” Which maybe was its intention, to fuck him to death.

Holding him in place with its hands on his legs, Slim thrust into him. He screamed as his magic was forced to expand around both its cocks as it hilted inside him. Oddly it was more pleasurable than painful, his pussy seemingly far more resilient than he would’ve thought. Was that natural though or because of its venom?

Its cocks twitching inside him, the lamia shuffled a bit before pulling out, the walls of Stretch’s pussy hugging tight around its cocks as if not wanting to let them go. And his body _didn’t_ want to let go of them, his magic screamed to remain full and stretched.

It thrust back in, making him yelp again. Clearly unused to mating with a different species, its pace was awkward and sloppy. It was unsatisfying and gave Stretch _far_ too much time to be fully aware of what was being done to him. Unable to fight and unable to beg for it to stop, he lay limp and sobbed instead, which only made it harder for Slim to fuck him.

Eventually with an angry sounding hiss it pulled all the way out, leaving Stretch’s magic aching with emptiness and need. If it was giving up altogether he’d have to take care of it himself with his fingers regardless of how _awful_ this situation was.

It uncoiled its body from around him, letting him lie on blankets of the nest. It left and he curled up around himself, quivering with relief. It wasn’t going to finish raping him. All he had to do was work his way through his arousal and then leave even if that meant crawling away. But despite how much his body burned he was repulsed by the thought of touching himself. … He’d just suffer through it then.

Arms scooped him up… Slim was back. It nuzzled its forehead against his. He cringed but managed not to whimper this time even when its tongue flickered against his face with soft hiss. It then placed him down on his front. He lay there for a couple seconds before it pulled him up… onto his hands and knees.

The head of its cocks were suddenly brushing against the lips of his pussy again. He didn’t even have time for a whimper before they rammed into him, buried all the way inside even though his magic had to squeeze them tightly together. They still felt good though, making his scream not entirely of despair and pain.

This time the pace Slim set was rhythmic and steady. Unlike before Stretch’s magic was on level with Slim’s without him having to lift his hips for it, making the process easier and far more pleasurable. Tears leaking from his eyes, Stretch rolled with the lamia’s thrusts to get maximum pleasure out of them, his body was too aroused not.

It brought him to a quick climax. Intense waves of pleasure rolled through him as his magic clamped around Slim’s cocks as they continued to pound into him. He came down panting and drooling, moving and more with Slim’s thrusts as he braced himself on one forearm.

This was all _wrong_. He disgusting for… cooperating and finding pleasure in this. But his body _needed_ this, he didn’t have enough willpower to resist even by going limp and trying to hold back his loud moans and grunts.

He soon came again and then a third time. Each one better than the last even as his pussy started to hurt a little more.

His mind was still clearer than he’d like. He’d rather be lost completely in animalistic pleasure than still be aware of how he was being violated and unable to do anything about it or the fact that it felt exceedingly good.

Slim was thrusting into him faster and harder though. That had to mean it was almost done and thus this nightmare would be over soon, right? Stretch could only hope.

It came with a loud hiss as it hilted itself inside Stretch. Warmth flooded his magic as its cocks twitched inside him, triggering another round of intense pleasure rolling through him. He came down to the feel of its cum still pumping into him, some of it oozed out around its cocks but the continued presence of his abdomen meant a lot more of it would be pouring into his belly, _gross_. There was _no_ way he could get pregnant from a lamia, right? … Right, they were snakes meaning they laid eggs, skeletons didn’t, meaning there were no eggs inside him for its cum to fertilize.

Thankfully it lasted maybe half a minute at most. Slim’s cocks were still erect inside him. It couldn’t… go again, could it? There was no way Stretch could take that… except he could, the arousal was dying down but it was still there, his body wanted more even if he was rapidly growing sore and overstimulated. And he was helpless to stop it from using him to its complete satisfaction.

It didn’t move for several long grueling seconds before pulling out, leaving Stretch’s pussy empty and dripping with its release as well as his own and arousal. It thrust back in, pulling a half yelp, half sob of despair and pleasure out of him. It was only one of its cocks though, the other was still erect though and pressed against his clit. And once it was pressed all the way in it stayed there, Slim’s grip on his hips more rigid then before. What was going on?

They stayed like that for several long minutes, Stretch too scared to move, before something changed. The base of the cock inside Stretch expanded until it was big enough to stretch his pussy. It was uncomfortable but nothing he couldn’t take with only one cock inside him, at the least the lamia was merciful in that sense, not that it counted for much.

The expansion in its cock traveled further down but when it was nearing the tip the base shrunk to normal size again. It was almost like something was passing through it. A second that _something_ was pushing out of the tip of Slim’s cock and into Stretch’s magic.

It was hard and soon there was enough pressure – it didn’t take much – for it push through the opening into his forcibly conjured womb. He whimpered as it settled inside him. What was it? Did he dare check? There was already another bulge forming in its cock inside him. Another _thing_? Or something else? Like a knot maybe, he’d rather it pump him full of cum over pumping anything else it might possibly pump into him.

It wasn’t it knot but another _thing_ it forced all the way through and into his womb. Right away there was another bulge. He did _not_ want to know what they were but…

He pushed himself up and put the top of his head on the blanket covered floor behind where he still braced himself with his forearm. Through his translucent orange ecto-flesh he could see the lamia’s burnt orange cum in his belly along with two… _egg_ shaped objects. The third was just reaching the end of his passage and pushed through into his womb too. It settled inside him and he screamed as loud as his now hoarse voice could go.

He looked back up and jerked away from the wretched lamia. Its grip was tight though, holding him firmly in place as another one of its _eggs_ in its dick stretched Stretch’s magic out.

“No, no, please _no_ ,” he begged when that egg was forced into his womb too. A second later another was on its way “Don’t do this, ya can’t fucking do this to me _please_.”

He clawed at the blankets in a vain attempt to pull himself off Slim’s _foul_ cock and away from its _foul_ eggs, not that he had any hope of escaping the ones already inside him. It was strong and there was nothing he could get a firm grip onto and to top it all off the arousal still pounding in his magic and soul along with the exhaustion left by four powerful orgasms in a row had him too tired to fight hard or long.

It wasn’t long before he had to give up. He went limp, sobbing with what little strength he had left as it filled his belly with its eggs.

The process was dreadfully slow, only one went through at a time, but it wasn’t long before he could feel the weight of the eggs in his belly. He didn’t dare look again, he didn’t want to see them in his womb, making it expand a little more with each one. But the bigger and heavier his middle got the more ill he felt, he might have vomited if it wasn’t for the fact that he hadn’t eaten in a while.

His sobs eventually petered out and tears leaked silently down his face. If only he could pass out, that way he wouldn’t have to feel the eggs being pumped into him or the awful growing weight in his middle. The only thing keeping him from collapsing was the lamia’s hands on his hips, holding him firmly on its cock. He would’ve far preferred it keep fucking him, even if he could get pregnant from that at least it wouldn’t be _eggs_. Those were far worse than a mere souling.

After what felt like _years_ there finally reached a point where when one egg slid into his womb another one didn’t bulge out the cock inside him. In fact, Slim pulled out.

“P-please be done. Please, no more.” His voice was even more hoarse and choked than before. He didn’t need to look to know his belly was bloated with eggs, he could feel it hanging down, stretching his ecto-flesh out as if he were pregnant. Which he was, right? With _eggs_.

Slim shifted behind him, still holding his hips up in its firm grip. It thrust into him presumably with its other cock, as there was just one again.

“Just sex, please just sex, please…” Stretch cut off with a choked sob as the base of its cock bulged out with the now very familiar feel of an egg. “Why me? Why, god why?” He sniffled, pressing his face into the blankets beneath him, the stench of snake that clung to them didn’t bother him anymore.

Slim let out a long string of hisses as its egg settled in Stretch’s womb and another one started making its way down. How many eggs did it have? Was it going to lay _all_ of them inside Stretch? Most likely. What if there were enough to stretch his ecto-womb to its limit and his belly would burst? … That would perhaps be better than carrying them. What if they could never hatch because they were different species and he would be forced to carry them in his womb for the rest of his life? If so he’d rather die here and now so maybe he _hoped_ there would be enough eggs to split his belly open. It would hurt but it would probably be a fast death.

The weight in his belly kept growing. If he closed his eyes when an egg pushed into his womb he could feel his ecto-flesh stretching a little more to accommodate it as it settled in. It started to hurt; his womb wasn’t meant to expand so quickly. It didn’t feel dangerous yet though. Maybe it would soon.

How far could ecto-flesh stretch before broke? Quite far, right? It was magic after all, meaning it was far more resilient than normal flesh. Normally that was a good thing but right here and now when he wanted to die it wasn’t; there was a _very_ real chance Slim would run out of eggs before his womb burst open, leaving him doomed to carry them until they hatched or for forever.

Thankfully the arousal was fading, helped along by the disgust he felt for the eggs in his belly. It was a small condolence. He might have been able to fall asleep if the growing weight in his middle wasn’t growing increasingly more and more uncomfortable with each egg. The way he was slumped on his front only his hips held in the air by Slim made his belly brush against the blanket nest beneath him, meaning he was quite big and getting bigger. Assuming he survived this, would he be able to walk when his ankle healed?

He might end up finding out as when his belly was full enough to settle firmly on the nest beneath, one more egg settling inside him, there wasn’t another one to take its place. Slim pulled out but still kept hold of Stretch’s hips. Several horrible long seconds passed before it thrust back in with both cocks this time.

Stretch yelped as they filled him, the residual arousal made it pleasurable but the soreness made it far more painful. But… it couldn’t pump more eggs into with both its dicks at the same time, that _would_ rip his pussy for sure. But it was already pulling to thrust back in. It was fucking him again. Why couldn’t it have just eaten him instead?

This time its pace was slow and gentle, Stretch would’ve called it loving if a partner he’d wanted had fucked him like that. The soreness in his pussy from being full for so long and the earlier fucking meant it still hurt though but not as much as it would’ve if it were fucking him with full force. Not that there that was much to be grateful for, he was still bloated with its eggs and getting raped again. He lacked the energy to protest even with words though so he just took it, doing his best to ignore the awful weight in his middle.

When Slim came it was with a loud hiss as he buried his dicks all the way inside Stretch with a slightly harsher thrust. They twitched as they squirted cum into him. The warmth flooding his pussy triggered another orgasm to roll through him. It wasn’t as intense as he previous ones but the waves of pleasure still erased the aches and pains in the rest of his body for a few glorious seconds.

He came down panting as Slim pulled out, allowing warm cum to ooze out his pussy, it was like a soothing balm inside the aching walls of his magic. Slim then carefully rolled him over onto his side and then back. He winced as the weight of the eggs settled on his spine, already aching due to the awkward angle his body had been forced into for however long. This _had_ to mean it was over though, he could rest at last. Maybe he would never wake up, hopefully at least.

He dispelled his magic, almost sighing in relief as the soreness in pussy vanish. The cum splatting onto his pelvis didn’t bother him but the way his womb sealed to keep the eggs in did. His body was accommodating them, not letting him dispel his abdomen. He was stuck with them.

Despite the fact that he _shouldn’t_ and knew it was stupid to do so, he titled his chin down to look at his middle. But even if he had smartly done everything in his power to _not_ look at it he would’ve eventually seen it anyway, it was too big to avoid seeing forever. It was round and big enough to make him look past his due date if it were carrying just a souling or perhaps pregnant with twins or even triplets. Which he would’ve _far_ preferred to the sight of however many eggs were inside him.

They were maybe about two and half times bigger than a normal large chicken egg. The outer ones were _far_ too visible, how far his ecto-flesh stretched made it even more translucent than it had been before. A fresh round of tears rolled down his face, he would’ve probably burst into sobs again if he had the energy to.

Slim hissed, flicking its tongue out of its mouth and looking what could only be described as happy. It bent over to put its hands to either side of Stretch’s swollen belly, making him flinch. It then nuzzled its forehead at its center, flicking out its tongue against Stretch’s ecto-flesh.

“Please stop, please.”

It ignored him of course and kept nuzzling his belly. He could’ve lifted his arms to attempt to push it off but he didn’t want to be in any kind of contact with it. Forcing him to lie there and endure the humiliation of what it had done to him and how happy it was about it.

Eventually it did finally stop though. But it wasn’t done torturing him. It scooped him up into its arms, making him whimper, and nuzzled its forehead against his, again flicking out its tongue to brush against his face.

It did that several times as it circled around the center of the nest before finally settling down. It then gently lay him in the coil its body made so that he was reclining back against its tail. Was it going to leave him alone to sleep? Seems so, it watched him silently.

He looked away and shifted to lie on his side, whimpering at the feel of the extra weight he had to move due to the eggs inside him. He closed his eyes tight and willed sleep to take his mind. With how tired he was it wouldn’t take long even though he was in the midst of his worst nightmare. He’d try to figure out a way to escape tomorrow or if he had to whenever his ankle healed, for now he just wanted the oblivion of sleep.

**Author's Note:**

> I will continue this probably soonish.


End file.
